Pattern-selecting devices for knitting machines

ABSTRACT

In a pattern selecting device for a knitting machine of a circular or flat or straight bar type there is provided a selection mechanism for cooperating with pattern butts to engage or miss the butts to determine a patterning cycle. The selection mechanism according to the invention includes one or more selectors in the form of an arm having a butt engaging face movable between butt-missing and butt-engaging positions, and an actuating part of magnetisable material movable between a pair of pole faces of or associated with a permanent magnet. The permanent magnet is located within an electromagnetic coil for magnetising the actuating part to attract it to one pole face and repel it from the other.

Savage et al.

1 PATTERN-SELECTING DEVICES FOR KNITTING MACHINES [75] Inventors: SidneyClifford Savage, Wigston Magna; Peter Sinclair Stock, Oadby, both ofEngland [73] Assignee: Wildt Mellor Bromley Limited,

Leicester, England [22] Filed: Dec. 14, 1972 [21] Appl. No.: 315,081

[30] Foreign Application Priority Data Dec. 20, 1971 Great Britain59155/71 Mar. 30, 1972 Great Britain 15006/72 [52] US. Cl. 66/50 R,335/234 [51] Int. Cl D04b 15/78 [58] Field of Search 66/50 R, 25, 75,154 A;

[56] References Cited UNITED STATES PATENTS 3,109,126 10/1963 Hailes335/234 3,154,728 10/1964 Bordenet 335/234 X 3,514,674 5/1970 Ito et al.335/234 X 3,550,398 12/1970 Widdowson 66/50 R 3,564,870 2/1971Glaunsinger 66/50 R Primary E.\'aminerWm. Carter Reynolds Attorney,Agent, or Firmlrving M. Weiner [57] ABSTRACT In a pattern selectingdevice for a knitting machine of a circular or flat or straight bar typethere is provided a selection mechanism for cooperating with patternbutts to engage or miss the butts to determine a patterning cycle. Theselection mechanism according to the invention includes one or moreselectors in the form of an arm having a butt engaging face movablebetween butt-missing and butt-engaging positions, and an actuating partof magnetisable material movable between a pair of pole faces of orassociated with a permanent magnet. The permanent magnet is locatedwithin an electromagnetic coil for magnetising the actuating part toattract it to one pole face and repel it from the other.

1 Claim, 17 Drawing Figures PATENTEUFEB I 1 I975 SHEET 30F 7 FIG.7.

PATENTEI] FEB] 1 I975 sum sor 7 PATTERN-SELECTING DEVICES FOR KNITTINGMACHINES This invention relates to pattern selecting devices forknitting machines.

While the invention is described hereinafter with particular referenceto circular knitting machines, it is to be understood that it is alsoapplicable to knitting machines of the flat and straight bar type.

Knitting machines comprise a plurality of needles which are associatedwith patterning butts, which may be on the needles themselves but aremore usually on lifting jacks for the needles or on operating presserelements for the jacks. The pattern butts are arranged so as toco-operate with selectors controlled by a pattern control mechanism soas to engage or miss the successive pattern butts to influence theaction or non-action of the successive needles to form a pattern.

In one particular form of patterning mechanisms, the needles are liftedby jacks having lifting butts springurged, preferably by the inherentspringiness of the jack, into a path for engagement with ajack raisingcam at each feed station, and retractable from that position by arocking presser which is rocked outwardly to cause retraction of theassociated jack and held in the outward position by a permanent magnet.The rocking pressers have, or are associated with, patterning buttswhich cooperate with selectors of a patterning device which either missthe butts or engage them whereby release of the presser from engagementwith the permanent magnet is effected with the consequent release of itsassociated spring jack, a butt portion of which returns to the path ofthe jack raising cam.

lt will be appreciated that such an arrangement is applicable tomachines with stationary or movable cam boxes.

The selectors are generally operated by some sort of electromagneticarrangement. It is also usual. to have the pattern butts arranged instaggered sets with a separate selector at each feed station associatedwith corresponding members of the sets. Thus, if there are six patternbutts in a set, each selector will control every sixth pattern butt. Theselectors at each feed station have to be stacked into a compact form,so that the bulk of the electromagnetic actuating mechanism has to bekept as small as possible, while ensuring that the action is fast andreliable.

It has now been discovered that a very effective form of selector isprovided if a magnetisable moving part of the selector operates betweenpole faces of a permanent magnet, when the pole faces themselves aresurrounded by an electromagnetic coil for actuating the moving part toone or other of the pole faces.

The present invention accordingly consists in a pattern selecting devicefor a knitting machine comprising a selector arm movable between a buttengaging position in which a face of the arm is engageable with patternbutts on or associated with needles movable relative to the patternselecting device, and a butt missing position in which the said facedoes not engage the pattern butts, the said selector arm furtherincluding an actuating part of magnetisable material movable betweenopposed pole faces of or associated with a permanent magnet, the polefaces being surrounded by at least one electromagnetic coil arranged tomagnetise the said actuating part for attraction towards a selected oneof the pole faces and repulsion from the other.

Is a simple coil is used, when a current is caused to pass through thecoil in one direction the said movable actuating portion of the armbecomes polarised in one sense and is attracted a first of said polefaces and repelled from the other of said pole faces and further, when acurrent is passed through the coil in the opposite direction, the saidmovable actuating portion of the arm becomes oppositely polarisedwhereby it is repelled from said first pole face and attracted towardssaid second pole face thus to be moved between positions in which thebutt engaging face of said arm lies in a butt engaging path or clear ofsaid path. It can be seen that the permanent magnet holds the actuatingpart in either position when there is no current flowing.

A separate coil may be used for each direction of magnetisation ifdesired.

The selector coils are preferably arranged in a stack forming apatterning unit, and the coils may be staggered for compactness of thestack. The coils may be shielded from each other by shelves so thatstray fields do not affect the operation of the selectors.

The pole faces may be formed on pole pieces extending from the permanentmagnet and straddling the actuating part.

In order to provide a compact coil with adequate tu'rns for theoperation of the actuating part, the coil may be long enough to embracethe whole assembly of permanent magnet and pole pieces.

The selector may be conveniently arranged so that the arm rocks about anaxis parallel with the axis of the associated coil.

The selector may be such that the arm is pivotable about one end.

Alternatively, the selectors may be such that the arm is pivotableintermediate its ends.

Some of the selectors in a stack may differ from others in the mode ofoperation in order to provide the same stroke of the face from a similarbut differently located, i.e. staggered actuating part and coil.

As an alternative to pivoting, the arm may have a flexible zone so thatone end may be fixed while allowing the movableactuating part to operatebetween the pole faces. The flexible zone may be formed by aberyllium-copper leaf spring.

ln a further alternative, the arm may be guided for sliding as themovable actuating parts moves between the pole faces. For example, thegap between the pole faces may be bridged by a non-magnetic elementhaving guides therein for the movable actuating part of the arm.

The selecting device may be used in conjunction with a patterningmechanism including the rocking pressers referred to above, but it willbe appreciated that it is also more widely applicable.

The invention will be further described with reference to theaccompanying drawings, which show a preferred embodiment of theinvention and modifications thereof, as applied to a circular knittingmachine of the rotating needle cylinder type, although it will beunderstood that the invention is more widely applicable.

In the drawings FIG. 1 is a perspective view with parts broken awayshowing the general arrangement of a stack of pattern selecting devicesaccording to one form of the invention;

FIG. 2 is a section through a cylinder of a knitting machine showing astack of selecting devices in situ;

FIG. 3 is a diagrammatic view of a selecting device of the stack and itsrelation to a coil would round a permanent magnet associated therewith;

FIG. 4 is a diagrammatic perspective view of a selecting device andpattern butts of the rocking pressure members in needle tricks of themachine.

FIG. 5 is a plan view generally in the direction of arrow V in FIG. 2;

FIG. 6 shows a modified selector device with the stack of selectingdevices differently located in relation to the machine axis;

FIG. 7 shows a modified form of selecting devices;

FIG. 8 shows a further modified form of selecting device;

FIG. 9 is a section taken along the line IX-IX of FIG. 8;

FIG. 10 is a front elevation of a further modified form of stack ofselecting devices;

FIG. 11 is a diagrammatic perspective view of two selecting devices asshown in FIG. 10;

FIG. 12 is a front elevation of a still further modified form of stackof selecting devices;

FIG. 13 is a view corresponding to FIG. 3 and showing a further modifiedselecting device of a stack;

FIG. 14 is an elevational view of the structure of FIG. 13.

FIG. 15 is a perspective view, partly exploded, of part of a modifiedform of stack of selecting devices;

FIG. 16 is an elevation on the arrow XVI of FIG. 15, and

FIG. 17 is a plan view, partly in section, of a further embodiment ofthe invention.

The invention pattern selecting device is suitable for use in a knittingmachine of the circular, flat or straight bar type and will hereinafterbe described in its application to a circular knitting machine of therotating cylinder type.

The illustrated machine comprises a cylinder 1, see

, FIGS. 2 and 5, in which needles 2 are supported in needle tricks 3provided in the wall of the cylinder 1. Also mounted in the needletricks 3 are needle jacks 4 which are each provided with a spring tailportion 5 having a lifting butt 6 arranged, when in an operativeposition, to engage a jack raising cam 7 when the needle 2 associatedtherewith is to effect a knitting operation.

The illustrative machine also comprises, associated with each jack 4, arocking presser member 8 normally held in an inoperative position by thespring-tail portion 5 of the associated jack 4. Each rocking presser 8has a pattern butt 9 and the pattern butts of each of the six successiverocking pressers are disposed in butt paths which lie one above theotehr, as may be seen in FIG. 4. The rocking pressers 8 each alsocomprise an upper end portion 21 arranged to engage a placer cam 23 inadvance ofa feed of the machine whereby-successive rocking pressers arepivoted to cause their end portions 21 to move outwardly (FIG. 2) intoengagement with a permanent magnet 24. Movement of the end portions 21into engagement with the magnet 24 is also effective, through a tailportion 25, thereof, to cause the butts 6 of the jacks 4 associatedtherewith to move clear of the jack raising cam 7 into the needle trick3 whereby actuation of the needle 2 is not effected, un-

- less the butt 6 is allowed to spring out from the trick by the presserbeing knocked off the magnet 24 as a result of selection by a patternunit 10 associated with the feed.

Each pattern unit 10, see FIGS. 1, 3, 4 and 5 comprises six buttselecting members 11 or cams pivotally mounted by a spindle 13 inbearings provided in a support housing of the device 10, each member 11having a butt engaging portion 12, the members 11 being arranged forpivotal movement, when the machine is in use, between positions in whichthebutt engaging portions 12 thereof lie in respective ones of the buttpaths or clear of such paths.

Each butt selector member 11 is pivotally mounted about a horizontalaxis in an associated bearing 13a in such a manner that the buttengaging portions 12 of each device lie one over the other (see FIGS. 1and 5), and movement thereof between said positions-is along a pathsubstantially at right angles to the said path of movement of anassociated pattern butt 9.

Each member 11 further comprises associated therewith (see FIG. 3) apermanent magnet 14 provided with upper and lower pole pieces 15 and 16,which magnet 14, together with the pole pieces 15 and 16, is arrangedwith a coil 17.

The coils and magnets are aranged in staggered relationship see FIGS. 1and 7 to maintain the stray flux effect between each magnet at a minimumand to provide for compactness of the arrangement. Shelves 17a ofmagnetic material are also provided to support and shield adjacent coilsfor extraneous electromagnetic field effects.

The butt selector members 11 are each further provided with actuatingparts formed of magnetisable material, herein referred toas'magnetisable actuation portions 18, which extend between the polepieces 15 and 16 of their associated magnets 14 in such a manner that,when on the one hand, the selector is in an inoperative position theportion 18 is held in engagement with the lower pole piece 16 of themagnet 14 and thus the butt engaging portion 12 thereof lies below apath of movement of its associated butt'9, and when, on the other hand,the selector is in an operative position and a current is passed throughthe coil 17 in one direction the actuating portion 18 becomes polarisedand is repelled from the pole piece 16 and attracted towards the polepiece 15 thus to cause movement of its associated butt engaging portion12 upwardly into a butt engaging path whereby a cam surface 20 of saidportion 12 is engageable by the butt 9. Engagement of the butt 9 withthe surface 20 is effective to cause rocking movement of the pressermember 8 associated therewith whereby the end portion 21 thereof ismoved away from the engagement 24 and consequently the spring tailportion 5 of the jack 4 moves the butt 6 into a path of engagement withthe jack raising cam 7 whereby an actuation of the associated needle 2is carried out.

The actuating portions of the selector members, although being shown asextending between the pole pieces 15 and 16 for a short distance seeFIG. 3, may be of such length that they extend wholly into the end spacebetween the pole pieces 15 and 16.

The pivoted butt selector members 11 are arranged in such a mannerbecause of the staggered relationship of the magnet and coilarrangements, that angular movement of the longer ones thereof comparedto the shorter ones thereof is compensated for by making the actuatingportions 18 of the shorter ones thicker compared to the actuatingportions of the longer butt selecting members. Thus movement of therespective butt engaging portions is maintained substantially the same.The same effect could be obtained by varying the distance between thepole pieces and 16 of the permanent magnets.

The magnet and coil arrangement has been found to operate mostadvantageously, compared with hitherto proposed arrangements, with theflux pattern concentrated around the actuating portion 18 and thepermanent magnet 14 in such a manner that the problem of stray fluxeffect on butt engaging members of other closely situated magnet andcoil arrangements is reduced. Further, the concentration of the flux issuch that a rapid action of the actuating member is obtained.

In a first modified arrangement, the pattern unit 10a see FIG. 6, isdisplaced by substantially a right angle, as compared with the device ofFIGS. 1 and 2, and the butt selector members lla thereof extendsubstantially radially of the machine cylinder. The butt engagingmembers each comprise a portion 12a arranged for movement betweenpositions in which it lies in the part of one level of butts 9a or clearof said path. The function of the magnet and coil arrangement issubstantially as hereinbefore described with reference to theillustrative selecting device. In both cases, the pivot axis of theselector is parallel with the axis of the coil.

In a second modified arrangement, see FIG. 7, the butt engaging membersare not pivoted but include a clamped spring member of beryllium-copperhaving an iron actuating piece (not shown) and a butt engaging portion32.

In a third modified arrangement see FIGS. 8 and 9, the butt selectormembers may be arranged as slide members located in slides 36 ofnon-magnetic material wherein, when on the one hand the member 35 isattracted towards one pole piece 37, of its associated magnet, it is inan operative condition in which a butt engaging portion is placed into abutt path, and when on the other hand the member 35 is attracted towardthe opposite pole piece 38, of its associated magnet, it is moved clearof said path.

In a fourth modified arrangement (see FIGS. 10 and 11) the butt selectormembers are arranged with alternate cones thereof as single armedmembers 40 or double armed members 41, so as to maintain the distancemovement by the butt engaging portions thereof at substantially the samedistance despite the staggering of the coils.

In a fifth modified arrangement (see FIG. 12) the butt selector members42 are of equal effective length and are arranged in a stack withalternate selectors pivoted on opposite sides of the selecting device.

In a sixth modified arrangement (see FIGS. 13 and 14) each buttselecting member 44 is located in an associated slot 5 formed in a block46 of the arrangement, said slot facing the magnet and coil associatedwith the butt selecting member 44 and acting as a pivotal location forthe member 44, a longitudinal pivotal edge portion 47 of the member 44being freely received within the slot 45.

The butt selecting member 44 is retained in the slot 45 by a pin 48passing through an oversized hole 49 formed in a lug portion 50 of themember, a center line of the hole 49 being arranged coincident with anedge of the portion 47.

The pin 48 also serves to retain each of the other five of the sixselecting members, of the sixth modified arrangement, in theirrespective slots 45.

Like the selecting members of the pattern unit 10 FIG. 1, the selectingmembers 44 each comprise a magnetisable actuation portion 52. However,in the sixth modified arrangement the portion 52 extends wholly into theair space between associated pole pieces 55 and 56 of a permanent magnet54 which pole pieces and actuation portion are arranged within a coil 57corresponding to the arrangement of FIG. 3.

Each selecting member 44 is also provided with a butt engaging portion58 arranged to function in a similar manner to the member 11 of FIG. 3with the exception that pivotal movement of the member 44 takes placeabout the edge portion 47 thereof located in the slot 45 as aforesaid.

FIGS. 15 and 16 show a modified form of the embodiment of FIGS 13 and14. An end block 61 is shown spaced from the housing 62 it completes tofacilitate the showing of the internal structure. The block 61 is shownas having two recesses 63 aligned with slots 64 in cooperating faces ofthe housing 62. Transverse grooves 65 are shown inthe cut-away portionof the block 61.

The butt-selecting or selector members 66 are each in the form of aspindle 67 snugly and rotatably received in two lengths of groove orslot 65. Each spindle 67 carries a hub 68 of a magnetisable actuationportion or actuating part or rocker 69 axially located in one or theother of the recesses 63. One end of each spindle 67 protrudes out ofthe side of the housing to carry a selector cam or rocker 70 on arespective hub 71.

As previously, the selector cams 70, having butengaging protions similarto the portions 12 described hereinabove, cooperate with pattern butts72 in tricks 73 of a needle cylinder 74.

The operation is similar to that of the FIGS. 13 and 14 embodiment,except that the movement of the buttselecting members 66 is moreprecise, by virtue of the cooperation between the spindles 67 and hubs68 with the corresponding formations in the end blocks 61. Thus it canbe seen that each selector member is in the form of a shaft freelymounted in a slot for rocking movement and carrying rockers forming theactuating part and butt-engaging portion.

FIG. 17 shows a further modification within the scope of the invention.Each selector is mechanically very similar to that shown in FIGS. 10 and11 of our United Kingdom patent specification 1,187,911 and consists ofan arm 81 shown in full lines in an operative position in the path ofpattern butts 82 .on a needle cylinder 83 rotating in the direction oftha arrow 84. The inoperative position is shown dotted at 81a. The armis rockable on a fixed pivot 85 by means of an actuating part 86 ofmagnetisable material extending between pole pieces 87 of a permanentmagnet 88. The actuating part acts as an armature in an electromagneticcoil 89 surrounding the magnet 88 and pole pieces 87, so as to movebetween the pole pieces and to be retained by them in either endposition.

Each of the foregoing selecting devices can be operated, to causepatterning to be effected on fabric produced on the machine, by signalsfrom a tape controlled means which may be similar to that disclosed inthe Specification of United Kingdom Patent No. 1,214,691 although anylike suitable means may be used.

It will be appreciated that the spring jack system (using rockingpressers) for operating the knitting needies is given by way of exampleonly. The electromagnetic selecting device according to the inventionmay be applied to other knitting systems e.g. where the patterning buttsare formed on the spring jacks themselves or on needle jacks which arerockable within the needle tricks.

Various modifications may be made within the scope of the invention. Forinstance, instead of a single coil adapted to be selectively energizedin one direction or the other, two separate coils e.g. wound together,could be used to magnetise the actuating portion.

We claim:

1. In a pattern selecting device for a knitting machine, comprising astack of selector members each having a butt-engaging portion movablebetween a butt-engaging position in which it is engageable with patternbutts on or associated with needles movable in relation to said patternselecting device, and a butt-.

missing position in which the butt-engaging portion does not engage saidpattern butts; the improvement that each selector member comprises anactuating part formed of magnetisable material and that the selectingdevice further comprises, associated with each selector member, apermanent magnet, pole pieces on said permanent magnet, opposed polefaces on said pole pieces, and an electromagnetic coil surrounding saidpermanent magnet and pole pieces, said actuating part of each selectormember being movable transversely of the coil between the associatedpole faces and being magnetisable by the associated coil for attractionto a selected one of the pole faces and repulsion from the other of thepole faces, and in that each selector member comprises a spindle freelymounted in a slot for rotational movement, each spindle carrying arocker forming the said actuating part and a rocker forming thebutt-engaging portion each rocker angularly extending from the spindlein the direction in which the said mounting slot opens.

1. In a pattern selecting device for a knitting machine, comprising astack of selector members each having a buttengaging portion movablebetween a butt-engaging position in which it is engageable with patternbutts on or associated with needles movable in relation to said patternselecting device, and a butt-missing position in which the butt-engagingportion does not engage said pattern butts; the improvement that eachselector member comprises an actuating Part formed of magnetisablematerial and that the selecting device further comprises, associatedwith each selector member, a permanent magnet, pole pieces on saidpermanent magnet, opposed pole faces on said pole pieces, and anelectromagnetic coil surrounding said permanent magnet and pole pieces,said actuating part of each selector member being movable transverselyof the coil between the associated pole faces and being magnetisable bythe associated coil for attraction to a selected one of the pole facesand repulsion from the other of the pole faces, and in that eachselector member comprises a spindle freely mounted in a slot forrotational movement, each spindle carring a rocker forming the saidactuating part and a rocker forming the butt-engaging portion eachrocker angularly extending from the spindle in the direction in whichthe said mounting slot opens.